Guide Thanks for joining us today. Let's start with a broad question: what would you call the "Golden Age" of rap?

Rakim The golden age was when people were starting to understand what hip-hop was and how to use it. I was lucky to come up then. Everybody wanted to be original and have substance; it was somewhat conscious …

There was an integrity that people respected. I'm just glad that it's circulating all over the world, because I used to hear: "Rap's a fad, it will probably be dead in 10 years, like jazz."

I can't look at TV without seeing something that's been influenced by rap. Even commercials for cereal. When I was small, I was a fan of cartoon characters – now the cartoon characters are rapping!

Wretch Being 26, I got memories of my dad listening to hip-hop. When you're young it's the catchiest stuff that catches your ear. Later, I found myself going back to older stuff, people like [Rakim], Sugarhill Gang and Run DMC. It's a privilege to be able to hear how it started.

Guide Did you both have musical childhoods?

Rakim My mother sang jazz and opera – she even performed at the Apollo on Amateur Night. Rapping was for the older kids. The Fatback Band's King Tim III was the first rap record [in 1979]. But he [Tim Washington] seemed like an old dude.

Wretch My dad was a reggae DJ, and one day he took me to see him on the mic. I looked at how he got control of the rave, just from his voice and what he played. It was like he had powers, man.

Rakim I'd see the MC come up to the park, grab the mic and start rockin'. He controlled the crowd. I thought I was flash, so I loved DJing, but the MC got all the attention, so I switched over. Tapes of Cold Crush 4, Treacherous Three and Grand Wizard Theodore would circulate, and I'd be clamouring to understand this rap shit.

Rap legend Rakim. Photo: Chris Buck/Corbis Outline

Guide In rap circles, there's an obsession with who is the "GOAT" – the Greatest Of All Time. Rakim, you often figure high in those lists. How does that feel?

Rakim You don't want it to get to your head, but you've got to respect the title that people give you.

Guide Do you respect the other rappers in those countdowns, people like Nas, Eminem, Notorious BIG, 2Pac, Jay-Z … ?

Rakim As long as my name is in there, I don't care who else is on the list! I love Biggie, he said a lot of things I couldn't say. I love Pac because he was revolutionary, he was militant. Eminem is a master. I love what Jay did, coming into the game and being one of the best rappers, then taking it to the next level as a business.

Guide Do you feel bitter at all that Jay-Z capitalised on the work you did in the 80s?

Rakim Nah. If that was the case then I would expect James Brown to be upset with me for sampling him. You never know. In 10 years' time, he [Rakim points to Wretch] may make Jay-Z's payroll look small. But I wouldn't change nothin'. If I was 17 now I'd still be an underground artist.

Wretch I'm still underground. I always check the underground websites to see who I've missed out on. I started on the floor and I'm working my way to the ceiling. But you can't ever forget about the floor.

Guide Rakim, I've read that you sometimes write backwards from the hook, or that you pick, say, a dozen words that then form the basis of the song. Do you have a particular method?

Rakim There are so many different ways to write.

Wretch I start playing a beat, and I get a vibe from it. Sometimes I come up with the hook first. Or sometimes something can happen, like my baby mama can just piss me off! As soon as she does, I hang up the phone and press play. I keep it real so that a lot of people can relate to it. I have girls telling me I need to make a song like Waka Flocka. But that's not the type of MC I am.

Guide Wretch, you put a lot of your own experiences into your songs – for instance, growing up on the Tiverton estate in Tottenham, where you witnessed stabbings and were involved in some shady dealings. Is that kind of authenticity important?

Wretch Yeah. There's a million people coming from the same place as me who are going to like it, because that's what they know. But there are another million people who have never been on an estate and might want to know what it's like. Listening to my music takes them there without actually having to go.

New kid on the block … Wretch 32. Photo: Suki Dhanda for The Observer.

Rakim I'm totally the opposite – I don't put too much of my personal life in my music. My understanding of rhyming is the exaggerated thought. To this day it's hard for me not to tell everybody how nasty I am on the mic! [Laughs] As soon as I pick up a pen I want to tell everybody how dope I am.

Guide There are now 30 years of rap to draw from. Is this a help or a hindrance?

Wretch I look at it like one big race, and everyone from the early generation has trusted us and passed us the baton. The goal is for us to prove this is one of the best genres anyone has ever heard, period.

Rakim I'm a little depressed by the state rap is in, but I try not to focus on the bad. Rappers for the last 10 years have been talking about gun play, but 99.9% of them ain't living it. If I was a murderer, I wouldn't have no time to write no rhyme about it.

Guide Rap has always revelled in saying things that might otherwise be taboo though. Doesn't it need to retain that quality?

Rakim But there's always a limit. It's important to do it artistically. I'm not saying seeing blood is appealing, but

the first thing you do when you hear someone got killed up the block is hurry over. But if you do it to the point where it's distasteful and influencing kids, that's not right.

Wretch Eminem will say things about chainsawing his granny but with him it's like science fiction. Art is art. Like in a film: you go and see The Terminator but you don't come out wanting to shoot someone in the head. It's entertainment.

Rakim That's right. We know a movie is entertainment. They get a lot of slack with regard to the violence. But if a rapper does it – if he says, "I'm a killer, I'm going to rob you and shoot you" – it's taken as autobiography. And now, what's happening is little kids go, "You steal my candy, Imma kill you … "

Wretch 32's single Don't Go is released on Sunday. Channel 4's Street Summer Season continues until Monday, celebrating street art, hip-hop and urban culture in the UK. See channel4.com/streetsummer for full details